Dataset Information

Explaining better hearing in Norway: a comparison of two cohorts 20 years apart - the HUNT study.

ABSTRACT:

Background

The hearing function at a given age seems to have improved in more recent born cohorts in industrialized countries. But the reasons for the improvement have not yet been explained.

Methods

We investigated the extent to which better hearing in Norway is attributed to modifiable risk factors by using representative demographic and audiometric data from two cohorts of the Trøndelag Health Study, HUNT2 (1996-1998) and HUNT4 (2017-2019). We estimated natural indirect effects using causal inference methods in order to assess whether cohort improvement in hearing thresholds (HTs) was mediated by occupational noise exposure, recurrent ear infections, smoking and education.

Results

The improvement in HTs from HUNT2 to HUNT4 was 2.8 and 3.0?dB at low respectively high frequencies. Together all risk factors mediated this improvement by 0.8?dB (95% CI 0.7-0.9) and 0.8?dB (95% CI 0.7-0.9) respectively, corresponding to mediated proportions of 27 and 28%. Substantial mediation was specifically found for occupational noise in men and recurrent ear infections in women (mediated proportions of 11 and 17% at high frequencies, respectively).

Conclusions

Increased education, less occupational noise exposure, ear infections and smoking contributed considerably to better hearing in Norway the last two decades.

SUBMITTER: Engdahl B

PROVIDER: S-EPMC7844976 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Explaining better hearing in Norway: a comparison of two cohorts 20 years apart - the HUNT study.

Engdahl Bo B Stigum Hein H Aarhus Lisa L

BMC public health 20210128 1

<h4>Background</h4>The hearing function at a given age seems to have improved in more recent born cohorts in industrialized countries. But the reasons for the improvement have not yet been explained.<h4>Methods</h4>We investigated the extent to which better hearing in Norway is attributed to modifiable risk factors by using representative demographic and audiometric data from two cohorts of the Trøndelag Health Study, HUNT2 (1996-1998) and HUNT4 (2017-2019). We estimated natural indirect effects ...[more]

PMID: 33509127

Similar Datasets

Project description:BackgroundA rapidly increasing proportion of people in high-income countries are surviving into their tenth decade. Concern is widespread that the basis for this development is the survival of frail and disabled elderly people into very old age. To investigate this issue, we compared the cognitive and physical functioning of two cohorts of Danish nonagenarians, born 10 years apart.MethodsPeople in the first cohort were born in 1905 and assessed at age 93 years (n=2262); those in the second cohort were born in 1915 and assessed at age 95 years (n=1584). All cohort members were eligible irrespective of type of residence. Both cohorts were assessed by surveys that used the same design and assessment instrument, and had almost identical response rates (63%). Cognitive functioning was assessed by mini-mental state examination and a composite of five cognitive tests that are sensitive to age-related changes. Physical functioning was assessed by an activities of daily living score and by physical performance tests (grip strength, chair stand, and gait speed).FindingsThe chance of surviving from birth to age 93 years was 28% higher in the 1915 cohort than in the 1905 cohort (6·50% vs 5·06%), and the chance of reaching 95 years was 32% higher in 1915 cohort (3·93% vs 2·98%). The 1915 cohort scored significantly better on the mini-mental state examination than did the 1905 cohort (22·8 [SD 5·6] vs 21·4 [6·0]; p<0·0001), with a substantially higher proportion of participants obtaining maximum scores (28-30 points; 277 [23%] vs 235 [13%]; p<0·0001). Similarly, the cognitive composite score was significantly better in the 1915 than in the 1905 cohort (0·49 [SD 3·6] vs 0·01 [SD 3·6]; p=0·0003). The cohorts did not differ consistently in the physical performance tests, but the 1915 cohort had significantly better activities of daily living scores than did the 1905 cohort (2·0 [SD 0·8] vs 1·8 [0·7]; p<0·0001).InterpretationDespite being 2 years older at assessment, the 1915 cohort scored significantly better than the 1905 cohort on both the cognitive tests and the activities of daily living score, which suggests that more people are living to older ages with better overall functioning.FundingDanish National Research Foundation; US National Institutes of Health-National Institute on Aging; Danish Agency for Science, Technology and Innovation; VELUX Foundation.

Project description:BACKGROUND:Cognitive impairment is a major contributor to mortality among the elderly. However, the relationship between cognitive impairment evaluated by educational levels and mortality and the trend between cognitive impairment and mortality with time are unclear. We aim to evaluate the differences in associations of cognitive impairment, taking the stratification by educational levels into account, with all-cause mortality and further explore the relationship of cognitive impairment with mortality in different age and sex groups in two cohorts ascertained 6?years apart in China. METHODS:A total of 13,906 and 13,873 Chinese elderly aged 65?years and older were included in the 2002-2008 and 2008-2014 cohorts from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Mortality data was ascertained from interviews with family members or relatives of participants. Cognitive function, evaluated by the Mini-Mental State Examination (MMSE), were defined by different cut-offs taking educational background into account. Cox models were used to explore the relationship of cognitive impairment with mortality. RESULTS:For the 2002-2008 and 2008-2014 cohorts, 55,277 and 53,267 person-years were followed up, and the mean (SD) age were 86.5 (11.6) and 87.2 (11.3) years, respectively. Compared to normal cognition, cognitive impairment was independently associated with higher mortality risk after controlling for potential confounders, with hazard ratios (HRs) of 1.32 (95% confidence interval [CI], 1.25-1.39) in 2002-2008 cohort and 1.26 (95% CI, 1.19-1.32) in 2008-2014 cohort, stratified by educational levels. The trend of cognitive impairment with all-cause mortality risk decreased from 2002 to 2008 to 2008-2014 cohort, while no significant interaction of cognitive impairment with cohort for all-cause mortality was observed. The associations of cognitive impairment and mortality were decreased with age in the two cohorts. CONCLUSIONS:Cognitive impairment evaluated by different cut-offs were associated with increased risk of mortality, especially among those aged 65-79?years in the two cohorts; this advocates that periodic screening for cognitive impairment among the elderly is warranted.

Dataset Information

Explaining better hearing in Norway: a comparison of two cohorts 20 years apart - the HUNT study.

Background

Methods

Results

Conclusions

Publications

Explaining better hearing in Norway: a comparison of two cohorts 20 years apart - the HUNT study.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets